1) I don't think it's known how big the "addictive" effects are. Meaning, if you use it a lot, you might get "used to it"(downregulation), and require more to get the same effect. See the link at the bottom; My doctor told me not to use it more then 4-5x a week; I have anecdotal evidence of it being less effective from my use
2) It might not be as effective as you're making it. It surely isn't as simple as "replacing the melatonin you're lacking". Melatonin you naturally produce happens in a series of step; the melatonin you take via a pill surpasses some of these steps, which means there isn't the same effect.
2) It might not be as effective as you're making it. It surely isn't as simple as "replacing the melatonin you're lacking". Melatonin you naturally produce happens in a series of step; the melatonin you take via a pill surpasses some of these steps, which means there isn't the same effect.
See http://www.supermemo.com/articles/sleep.htm#Melatonin